This invention relates to methods and systems for coding alternate fields of an interlaced video format and has particular applicability to arrangements wherein the other fields have already been coded.
Interlaced scanning is an efficient method of bandwidth compression for television transmission. Further bandwidth compression can be achieved by downsampling the interlaced video sequence by deleting either all the even or all the odd fields. This scheme is used, for example, in the current Motion Picture Experts Group (MPEG) proposal relating to coding and decoding protocols for the compression of video data. In that proposed format only the odd fields of an interlaced video sequence are encoded and transmitted. The present invention, utilizing the fact that even and odd fields are highly correlated, makes it possible to code the missing even fields very efficiently.
It is therefore the object of this invention to provide methods and systems for efficiently coding one field of an interlaced video.
It is a further object of this invention to provide methods and systems for coding interlaced video data so as to permit efficient and accurate decoding using methods and systems also in accordance with the invention.